NEW YORK, Oct 1 (Reuters) - U.S. stocks rose at the start of the last quarter on Monday on a surprise expansion in the U.S. manufacturing sector last month and bets central banks will continue to support markets.

The U.S. manufacturing sector expanded in September, shaking off three months of weakness as new orders and employment picked up, an Institute for Supply Management report showed.

The figure came after a survey from Markit showed U.S. manufacturing ended its worst quarter in three years in September as foreign demand for U.S. goods fell sharply.

The weak U.S. data followed surveys in the euro zone that showed manufacturing slackened in the three months to September while Asia's factories are continuing to struggle in the face of tepid demand from the United States and Europe. The data flagged a return to recession for the euro zone and a seventh straight quarter of slowing growth in China.

"The U.S. economy is growing at a slow pace, but it is still growing. The ISM number suggests that things are not that bad. We're not quite at the point where things are good, but this indicates strongly that things are not so bad," said Adam Sarhan, chief executive at Sarhan Capital in New York.

"Despite a recent spate of weaker-than-expected data from across the world, markets are looking forward. There is a lot of hope that the worst-case scenario is off the table not only for now, but for good."

Equity markets are also being supported by expectations of support from central banks including the Federal Reserve and the European Central Bank, which are partly offsetting weak data.

The Dow Jones industrial average

gained 136.55 points, or 1.02 percent, at 13,573.68. The S&P 500 was up 15.07 points, or 1.05 percent, at 1,455.74. The Nasdaq Composite

rose 27.77 points, or 0.89 percent, at 3,144.00.

Ceradyne Inc

shares gained 43 percent to $34.92 on news the company will be acquired by 3M Co for $847 million.

Financial stocks led the market's advance with Goldman Sachs Group

up 4 percent at $118.19 after the weekly Barron's said Goldman shares could rise at least 25 percent in the next year as capital markets improve.

The U.S. Defense Department on Friday awarded United Launch Alliance, which is a 50-50 joint venture of Lockheed Martin Corp